Markup

Looking at just the dropdown menu, here's the required HTML. You need to wrap the dropdown's trigger and the dropdown menu within .dropdown, or another element that declares position: relative;. Then just create the menu.

Dropup menus

Dropdown menus can also be toggled from the bottom up by adding a single class to the immediate parent of .dropdown-menu. It will flip the direction of the .caret and reposition the menu itself to move from the bottom up instead of top down.

Disabled state

For any nav component (tabs, pills, or list), add .disabled for gray links and no hover effects. Links will remain clickable, however, unless you remove the href attribute. Alternatively, you could implement custom JavaScript to prevent those clicks.

Text

Wrap strings of text in an element with .navbar-text, usually on a <p> tag for proper leading and color.

Optional display variations

Fix the navbar to the top or bottom of the viewport with an additional class on the outermost div, .navbar.

Fixed to top

Add .navbar-fixed-top and remember to account for the hidden area underneath it by adding at least 40px padding to the <body>. Be sure to add this after the core Bootstrap CSS and before the optional responsive CSS.